Today most ice rinks in Sweden use secondary Refrigeration systems with a solution of calcium chloride and water as secondary refrigerant. Due to the large amount of energy such a system uses more efficient systems would be desired.An earlier study concluded in the possibilities of using carbon dioxide as secondary refrigerant with copper tubes as the loops in the ice rink. Since then 3 ice rink Refrigeration systems has been built with carbon dioxide in copper tubes. Excluding the ones being direct involved in those projects there is still very little knowledge about how these system works. This study has been made primarily with the aim of adding to the knowledge concerning availability and cost and secondary to look at possibilities for improvement.A comparison between systems with carbon dioxide, calcium chloride respective ammonium solved in water has been made by using Decision Matrix.

The real estate company Ihus is facing an expansion of its comfort cooling in Noatun,Uppsala, to provide the buildings in the block with cooling. The buildings in Noatunare mainly used for office premises, where the requirements for an accepted indoorclimate is great. However, it?s uncertain whether Ihus should continue, as currently,producing comfort cooling by themselves using a compressor chiller, or if they shouldconnect themselves to Vattenfall?s district cooling net.The purpose of this report is to examine which technique of cooling is best suited forIhus and their buildings in Noatun. It should also work as a guideline for othercompanies facing the same problem as Ihus.

This thesis concerns an energy audit of a food industry. The company's business consists of boiling and peeling shrimps, and producing mayonnaise-based salads. This type of work involves energy-intensive processes, such as steam generation, compression of air and Refrigeration of large spaces. These needs are supplied with electricity. Furthermore, the industry is a major consumer of district heating, particularly for heating the supply air in the ventilation system.

The author has, with the help of AK Consultancy Indoor Air AB, formed a series of questions regarding moisture problems in buildings and how these are handled in extreme climates with high temperatures and a high relative humidity. Furthermore to analyse and indentify key material that makes a construction safe against moisture problems. Ventilation, AC and the choice of materials have in a later stage of the thesis been investigated to enhance the knowledge of moisture protection. The research for this report includes measurements on existing buildings, calculation models on the building envelope for analyses and the ingoing materials of the envelope. The health aspect of moisture problems related to ?sick building syndrome? has been included and interviews have been conducted to gather relevant information.A study of the American system, ASHRAE, American Society of Heating, Refrigeration and Air Conditioning Engineers and the standards used in Singapore has been made to highlight the difference.

This thesis examines different methods for the cooling of data centers. Several means of cooling with the Refrigeration cycle have been studied, as well as the feasibility of using free cooling in different parts of Sweden. In addition, the possibilities of transferring excess heat to a nearby district heating system were investigated. It was found that in all investigated cases except two, the data center could be cooled solely with free cooling for at least 300 days a year when only the outside air temperature was considered as a constraining factor. The limit was then set to 20 °C.The vast majority of all district heating systems in Sweden get little to none of their heat from other excess heat sources.

The fishing port of Bläsinge is located on the east coast of Öland, Sweden?s second largest island. Today the port has a limited supply of freshwater. The economic association of the fishing port wants to expand their business, so that they will also include tourist services. To do this the harbor will need a more independant source of freshwater, with a higher quality than the present well.

Within process or manufacturing industries, the production of goods and services or the products themselves may have negative side effects such as pollution. An important task for environmental policy is to control and limit these pollutions, for example via regulatory measures. Although, the efficiency of such measures vary greatly between different industries and an increasingly important task for environmental policy is then to encourage companies to engage in environmentally motivated innovation. Governments can utilize other measures than regulation to indirectly decrease pollution. This thesis aims to analyze such activities and how it affects the innovativeness of wastewater treatment, Refrigeration and automobile manufacturing industries.

Considering that the price and demand for energy gradually has risen over the past decade and a wider discussion about the human impact on the environment has become increasingly more important and given a clearer role in modern society. This has contributed to increased incentives to reduce the use of fossil fuels and increase the use of renewable energy.The agriculture currently accounts for 20 % of Sweden's total greenhouse gas emissions. A way for an agricultural company like Wapnö AB to reduce their emissions could be to utilize existing renewable energy sources within their own premises.The report's aim is to create an energy audit of Wapnö?s existing energy system and how it changes with a future biogas plant in operation. The energy audit is used to illustrate how the company?s climate footprint could change.

Diabetes mellitus is characterised by persistent hyperglycemia in all species. Fructosamine is a glycated protein reflecting blood glucose concentration during the preceding weeks. It has become a valuable analysis to differentiate persistent hyperglycemia from transient stress induced hyperglycemia in cats. It is also used to evaluate current therapy in diabetic patients. Although fructosamine is a well accepted analysis, it is sometimes regarded with scepticism.

This master thesis project at KTH is performed in the Mechanical and Aerospace Engineeringdepartment at University of Florida (UF). The thesis is a small part of a gas turbine researchproject where a vapour absorption Refrigeration system (VARS) and a high pressure regenerativeturbine engine (HPRTE) are integrated together. The main objective is to build a computermodel of the VARS. The computer model is supposed to be used to analyse the off-designperformance of the VARS and should also be easy to integrate as a subroutine in a more complexsystem model. To model the VARS some knowledge of the absorbent/refrigerant mixture had tobe well known, in this case a mixture of ammonia and water.

Kylmaskinerna på Saab ABs fastighet i Järfälla står för en stor del av den totala användningen av elektricitet i fastigheten. Därför är det viktigt att undersöka och analysera hur dessa kylmaskiner presterar i dagsläget och vilka åtgärder som kan vidtas för att förbättra prestandan.Detta examensarbete har fokuserat på hur kylmaskinerna i D-huset på Saab i Järfälla presterar. Därför har flera tester på dessa kylmaskiner utförts. Mätvärdena har huvudsakligen registrerats med ClimaCheck utrustning och uppmätt data har analyserats med datorprogrammen Refprop, Energy Equation Solver och Excel.  Undersökningar av kylmaskinerna i D-huset har visat på flera upptäckter. En upptäckt är att köldmedierna inte har rätt sammanställning.

Cooling down the indoor air can be done in several ways. One way is desiccantcooling which will be used at the Stockholm Arena. This method is used in airhandling units that use temperature changes and moisture fluctuations in the air. Oneof the steps is to add heat during the cooling process in order to reduce the relativehumidity of the exhaust air. The air passes thru an adsorptions rotor which thenabsorbs moisture from the supply air.

Energy supply in Sweden year 2011 amounted to 577 TWh. The final energy consumption for industrial, residential and service was 379 TWh. Sweden has energy policy goals to reduce energy use in buildings. One of these goals is to reduce the energy use by 20 % in 2020 compared to the year 1995. An important step to achieve this goal is to target energy efficiency measures in existing buildings.

Syftet med rapporten är att göra en jämförelse av två olika metoder för att kyla ett fiktivt kontorshus som är 2 000 m² stort och beläget i Västerås. För att representera ett normalt kontorshus har kyleffektbehovet valts till 50 W/m² vilket ger totala kyleffektbehovet 100 kW. I ena fallet finns en kylmaskin som kyler byggnaden och i andra byts kylmaskinen mot ett antal borrhål som motsvarar hela kyleffekten. För att kunna bedöma de tekniker som har använts har energianvändning och växthuspotential beräknats i ett livscykelperspektiv. Denna energianvändning beräknas som inbäddad energi, vilket är all energi som använts från framtagande av råmaterialen till färdiginstallerat system.